Pendulum scale



Mar. 6, 1923.

C. SIRCH PENDULUM SCALE Filed May 9, 1917 2 sheets-sheet l A TTOR/VEY Mar. 6, 1923.

C. SIRCH PENDULUM S GALE Filed May 9, 1917 2 sheets-sheet 2 INVENTOI? ATTORNEY 7 1/ Jill/[m VII/III Patented Mar. 6, 1923.

UNITED STATES CHARLE$ smor'r, or NEW YORK, N. Y.

PENDULUMI SCALE.

Application lied May 9, 1917.

To all whom it may concern Be it icnown that I, Crniizixns Sinori, a citizen of the United States, and a resident of New York city, in the county and State of New York, have invented certain new and useful improvements in Pendulum ticaics, of which the following a specification.

This inretion relates to a pcnduhun scale of novel construction, more particle larly adapted for analytical purposes and for weighing oil minute quantitie; such as milligrams. The minute weight units heretofore gei'ierally employed in scales of this class, are diiiicultto handle, are apt to become mislaid, and to suiter in bulk by abrasion. The scale which forms the subject matter ot this invention adapted to weigh o'lt' small quantities without the use oi any weight units, while for weighing larger quantities, weight units may be employed, so that the larger units only need be haudlcd. The invention comprises the various features of novelty more fully pointed out in the specification and appended claims.

In the accompanying drawi n Fig. 'l is a front elevation or r pendulum s ale embodying my invention;

Fig. 2, a longitudinal section through the post;

ilig. 3, a plan;

Fig. i, a. cross section through the post di rectly above the index; and

Fig. 5, a detail of one of the hangers.

From the base 1, furnished with leveling screws 2, extends a hollow post 3, which is provided at its upper end with a longitudinal slot 4., that opens into a. transverse slot 5. The top of post 3, carries V shaped bearings (3. that are engaged bv lmit'e edge 'lulcrun'is 7, mounted on the scale beam 8, and extending obliquely to the axis of the latter. From the center oi beam. 8. proim-t upwardly a number 0'! diverging screw rods 9. that carry threaded ballasting weights ll), by means of which the beam may be set true. From one end of the beam, depends a smaller'pan 11 for the reception of weights, while from the other end of the beam, depends a larger pan 12 for the reception of the load or substance to be weighed. Pans 11, 12 are suspemlei'l from the beam by means of intervening hangers 13 (Fig. (3) slotted forthe reception of the pan-carrying bails, and furnished with upper inverted V shaped bearings 14, engaged bykniie edges 13, that project upwardly from beam 8.

Serial No. 167,391.

From the center of beam 8, there depends into the hollow of post 3, a screw rod 16, that is secured to the beam by means of a slotted coupling 17, and carries an adjustable bob 18, confined between upper and lower nuts 19. To the lower end of screw rod 16, is connected by means of a nut 20, the upper bent end of a pendulum rod 21, which extends outwardly through transverse slot 5, while the main body of the pendulum is exposed and extends in its normal position (1. e. in its position of repose) vertically down along the front of post 3. The parts just described may he so conceived that screw rod 16, constitutes one member'ot the pendulum, of which rod 21 constitutes the other member, rod 16 during the play of the pendulum, being free to swing out of the hollow of stem 3, through longitudinal slot l. To the lower end of post 3, issecured by means of an inclined bracket 22', an arched scale or graduated index 23, which extends from the post in a direction coincident with the dip of knife edges 7 (Fig. 1). Over the index, sweeps a pointer 24: which is integral with pendulum rod 21., and is formed by defleeting the lower end of said rod into parallelism with the index. The index may be marked in suitable manner to clearly indicate milligrams or similar small units. With the embodiment shown, it is divided into five concentric belts, each in turn, be ing subdivided by transverse lines into grades representing say five milligrams, the lines in any one belt. being in stepped relation to those on the adjoining belts. By this arrangement, consecutive weights are represented by successive lines formed in successive belts, so that in this way, the scale may be read with great facility.

With the scale constructed as described, any sul'istauce placed into pan '12 will cause the corresponding end of beam 8 to descend, so that knife edges 7 will gradually swing into a. vertical position and pointer will travel over index so as to automatically indicate thereon, the weight of the load, the correlation of the parts being such, that the knife edges 7 will assume a vertical position, when the pointer arrives at or about the center of the index. If the entire length of the index represents the sweep of the pointer induced through the weight of one gram, that quantity may be weighed ofi, without placing any weights into pan 1.1. If however, larger quantities are to be weighed, weights representing whole grams or similar units are placed into the pan, which must be counterbalanced by the load placed into pan 12, before the pointer will start its travel along index to indicate any desired further fractions. Thus for weighing say 3 grams and i5 milligrams,

lace a three gram weight into pan 11, and add load to pan 12-, until pointer 2% ar rives at the l5 mark of index 23.

The scale constructed as described, is so delicate, that its beam is apt to vibrate for quite a length of time before coming; to a poise. In order to check thesi vibrant and thus save time, there is pivoted to i"), at 30, a two arm lever 31, irom one arn'i oi? which is suspended, a hand chain 32. From the other arm oi": the lever, there extends rearwardl a pin carrying a rub- Or) her or other cushioning sleeve 3%, adapted to engage the lower side of beam 8. litter a load has beenplaced on pan 12, a pull on the chain will project the cushioned pin against the beam, and by then slowly relaxing the pull, the pointer may be carried directly to the proper marl: on the index, with the elimination of objectionable 'vibrations.

Means are provided for locking the scale beam against pin 38, when the scale is not in use, thereby preventingthe knife edges from becoming unnecessarily worn. To this effect there projects forwardly from po directly above fulcrum 30, a stud to w arness is pivoted, a hoolr 86 having a cushioning sleeve 37 and adapted to be so turned by revolving hook 36 in stud 35 as to pass over beam 8, (in which position it is shown in Fig. 3) to hold it ag inst pin 33, thus locksaid beam. The downward movement oi the lever 31 is limited by the engagement of the stud 35 with a slotted extension 38 of said lever.

I claim:

1. A scale comprising a post, a beam tulcrumed thereto, a pendulum depending from the beam, said pendulum having a lower bent end to constitute an inclined pointer, and an inclined index extending sileways of the post and cooperating with said pointer.

2, A scale comprising a hollow slotted post, a beam 'Eulcrumed thereto, a pendulum h aving an upper member located within the post, and a lower member located outside of the post, said upper member carrying a hob, and an index cooperating with the lower member. i

3. A scale comprising a post, a beam fulcrumed thereto, a pendulum dependin from the beam, a lever pivoted to the post, said lever having; a slotted extension, :1 pin can ried by the lever and adapted to be projected beneath the beam, a stud on the post, adapted to be engaged by said slotted extension, and a hook pivoted to the stud and adapted to be projected over the beam.

CHARLES SIR CH. 

